1. Field of the Invention
The present invention relates to an AC plasma display panel and in particular to electrodes and ribs of an AC plasma display panel.
2. Description of the Related Art
A plasma display panel (PDP) is a thin type display, and typically has a large viewing area. The luminescent principle of the PDP is the same as that of fluorescent lamps. A vacuum glass trough is filled with inert gas. When a voltage is applied to the glass trough, plasma is generated and radiates ultraviolet (UV) rays. The fluorescent material coated on the wall of the glass trough adsorbs the UV rays, hence the fluorescent material radiates visible light including red, green and blue light. A plasma display can be described as a combination of hundreds of thousands of illuminating units, each illuminating unit has three subunits for radiating red, green and blue light, respectively. Images are displayed by mixing these three primary colors.
As shown in FIG. 1, a conventional PDP 10 has a pair of glass substrates 12, and 14 arranged parallel and opposite to each other. A discharge space 16 is formed between the glass substrates 12, and 14 and injected with inert gases, such as Ar, Xe or others. The upper glass substrate 12 has a plurality of transverse electrode groups positioned in parallel. Each group of transverse electrodes has a first and a second sustaining electrode 18 and 20, each of which includes transparent electrodes 181 and 201 and bus electrodes 182 and 202. A dielectric layer 24 is further formed covering transverse electrodes, and a protection layer 26 is formed on the dielectric layer 24.
The lower glass substrate 14 has a plurality of barrier ribs 28 arranged in parallel and spaced apart by a predetermined distance dividing the discharge space 16 into a plurality of groups of sub-discharge spaces. Each group of sub-discharge spaces includes a red discharge space 16R, a green discharge space 16G, and a blue discharge space 16B. Additionally, the lower glass substrate 14 has a plurality of lengthwise electrodes 22 disposed in parallel between two adjacent barrier ribs 28 serving as address electrodes. A red fluorescent layer 29R, a green fluorescent layer 29G, and a blue fluorescent layer 29B are respectively coated on the lower glass substrate 14 and the sidewalls of the barrier ribs 28 within each red discharge space 16R, each green discharge space 16G, and each blue discharge space 16B.
When a voltage is applied for driving electrodes, the inert gases in the discharge space 16 are discharged to produce UV rays. The UV rays further illuminate the fluorescent layers 29R, 29G, 29B to radiate visible light including red, green and blue light. After the three primary colors are mixed at different ratios, various images are formed and transmitted through the upper glass substrate 12.
FIG. 2 is a local top view of FIG. 1. Referring to FIG. 2, the ribs 28 are arranged in parallel and spaced apart from each other on the rear substrate. A discharge space 16 is disposed between the first sustain electrode 18 and the second sustain electrode 20. In the discharge space 16, the inert gas is ionized to strike the fluorescent layers on the rear substrate and the ribs 28 to generate light. However, only the fluorescent layers coated on adjacent ribs 28 can generate light, hence luminance of the PDP is not enough. Additionally, drawbacks of the open discharge space are that the adjacent discharge space 162 is prone to crosstalk, causing interference between cells and reducing the PDP 10 display quality.